Plugs are simple end-caps used to seal the open ends of structural galvanised tubes. They prevent entry of debris, moisture, or other materials into the tube interiors. The catalogue lists plug models by nominal bore (NB): PLUG15, PLUG25, PLUG30, PLUG40, PLUG50. Their installation is straightforward: they are pressed or inserted into the tube ends, providing a flush closure without protrusion, thereby preserving the aesthetics and functional integrity of the support frame.